This invention relates to a heat exchanger and particularly, but not exclusively to a heat exchanger for use in transmitting heat from warm contaminated air extracted from a building into fresh cold air drawn into the building.
In recent years, particularly in northern climates, much attention has been given to the development of heat exchangers for use in ventilating buildings while retaining a proportion of the heat in the extracted air. Devices of this type have significant advantages in animal husbandry where high levels of ventilation are necessary from a building to keep the contamination and moisture in the air to an acceptable level.
While these high levels of moisture and contaminants provide a high requirement for heat exchangers of this type, they also present serious problems in relation to the heat exchangers in view of the fact that the contaminants and moisture can be highly corrosive, and clog or block the heat exchange core and also can cause severe icing problems in view of the high level of moisture which condense as the contaminated air is cooled.
It is one object of the present invention, therefore, to provide an improved heat exchanger firstly providing an improved core construction which gives high heat transfer efficiency while being of a simple construction resistant to contamination and corrosion.
It is a second object of the present invention to provide a heat exchanger having a core which is of a design which can be self-cleaning, that is the contaminant and moisture collecting in the core are arranged to escape from the core without clogging or blocking the passage of the contaminated air.